Lamp starting device



Oct. 11,1932. PAETH 1,881,976

LAMP STARTING DEVICE Filed Jan. 18. 1950 CHARLES SPAET'H INVENTQR BY ATTORNEY Y pressing sired noise.

Patented Oct. 1 1 1932 UNITED STATES PATENT OFFICE CHARLES SPAETH, OF FLUSHING, NEW YORK, ASSIGNOR TO N E-ARGA CORPORATION, OF-

NEW YORK, N. Y., A CORPORATION OF NEW YORK LAM? STARTING DEVICE Application filed January 18, 1930. Serial No. 421,682.

possible, a complete absence of all unneces;

sary noises and electrical disturbances. Mercury arc lamps equipped with starting devices of the type known heretofore are unsuitable for use in the production of talking pictures because when one of the lamps becomes extinguished, the starting device thereof immediately starts to functionso as to reignite the lamp, thereby producing a clicking noise. The noise produced by the ordinary starting device is suflicient to cause aserious disturb'ance, which will be made part of the sound record. Likewise, when the starting device serves to create a momentary high" potential starting current, the starting current causes a disturbance in the recording of the sound if an electrical process is being used. This recording is'usually carried out by electrical recording apparatus, including a high power amplifier 1 which serves to amplify the sound currents picked up through microphones. These amphfiers are sufliciently powerful to pick up the disturbing electrical waves as well, thereby imon the recording medium an unde- In accordance with my invention I provide means responsive to initiation of operation of the lamp to render inactive the starting mechanism thereof so that .if the lamp later becomes extinguished, the starting device will be unable to function. The lamp will therefore remain unlit untilit is manually restored to operation at an opportune moment. I accomplish this result by providing relay means which serves to open the energizing circuit of the starting device upon the creation of a self-sustained discharge through the tube.

The objects and advantages of my invention and the manner of attaining them Willbe made clear in the following description make-and-break starting device of the wellknown type, and 3 indicates generally a relay mechanism for rendering inoperative the starting device 2 responsive to the initiation of normal operation of tube 1. 4 is a main line switch for controlling the energy supplied by power line 5.

When it is desired to put the'tube 1 into operation, the main line switch 4 is closed, thereby causing a potential to be applied across the electrode terminals. 6 and 7 of the tube; This potential, while sufiicient to maintain operation of the tube, is not sufficient to start such operation. Closure of the line switch 4 also, causes current to flow through conductor 8, ballast resistance 9, contacts 11 'of switch 12, current limiting resistance 13,

contacts 14 of switch 15, inductance coil 16 and back to the line. This current magnetizes the core of'the inductance coil 16', thereby causing it to attract the tiltably-mounted armature 17, to which is afiixed the switch 15. This tilting action causes the circuit to be broken'between the contacts 14. Upon breakage of this circuit a high potential'surge is set up by the inductance coil 16, which is applied to the terminals 6 and 7 of the tube 1, thereby causing the gas or mercury therein to be rendered conductive so that adischarge is initiated. Immediately after the discharge is created the operating potential necessary for the tube drops sufliciently to enable the tube armature 20 upon which the switch 12 is V mounted. This action causes the connection between contacts 11 to be broken, thereby rendering the starting mechanism 2 inoperative. Upon the attraction of the armature 20 power line ance 9. Should the discharge of the tube 1 now be extinguished, as by a cooling blast of air or a momentary change of line potential, the starting device 2 will'be unable to operate, because its energizing circuit is broken at 11. In order again to put the tube in operation, it is necessary momentarily to open the line switch 4, thereby deenergizing the holding coil 22 and permitting the contacts 11 of the switch 12 to close. The closure of these contacts permits the starting operation to be repeated in the manner above described. Upon tilting of the armature once or several times, a sufiiciently high potential is supplied to the tube to cause the discharge again to be created.

While I have shown a separate holding coil 22, it will be understood that a portion or all of the main coil 23 of the relay 19 might be used instead to maintain the contacts 21 closed. Y

The function of condensers 23 and 24 to prevent arcing at contacts 14 and 11- The condenser 23 also serves to increase the potential generated by the inductance 16.

As a result of the means and circuit connections which I have just described undesiredoperation of the starting mechanism of a gaseous discharge device may be prevented, once the line switch is closed and the tube initially put into operation. Further funcstarting mechanism is pre-- tioning of the vented until such time as it is desired, when it may be rendered operative again by opening the line switch momentarily and again closing it. It is therefore possible by such arrangement to prevent undesired audible and electrical disturbances which mi ht interfere'with the recording of sound e ects.

What is claimed is:

1. In a current supply system, an electric lamp, a source of power and a control switch therefor, a starting device having a circuit in shunt to said lamp, a switch therefor,wand means responsive to the starting of operation by said lamp, for opening and holding open said switch second mentioned, said means comprising an armature, an associated magnetizing coil connected between said lamp and said circuit, said magnetizing coil having a winding in series with said lamp, and 11. separate holding winding, and contact means responsive to the'opening of said switch second mentioned for energizing said holding windmg.

2. In a. current supply system, a lamp requiring means for reducing the starting resistance of the current path thereof, a power source and a control switch for said lamp,-a

starting device for performing the function above mentioned, and means responsive to the desired reduction in starting resistance for rendering said starting means ineffective un- January, 1930.

CHARLES SPAETH.

has 

